Barrell attended Assumption Catholic Secondary School in Burlington, Ontario, where she had a lead role in two school plays, in addition to collaborating with a friend on a play in which they wrote, directed and acted together. She directed her high school's production of The Wizard of Oz and was a member of Burlington Student Theatre for two years. She started studying musical theatre at Sheridan College but transferred and focused on acting studies at George Brown Theatre School, where she graduated. She also did some training at The Groundlings comedy school.
Barrell's television work includes made-for-TV movies Poe (2011) as Rowena, and Girls Night Out (2017) as Sadie. Guest appearances include Lost Girl in the episode "Table for Fae" (2012) as Maisie; Murdoch Mysteries in episodes "Murdoch in Toyland" (2012) as Marley Rosevear, and "The Murdoch Appreciation Society" (2014) as Ruby Rosevear; Saving Hope in the episode "Can't You Hear Me Knocking?" (2015) as Dixie Kolesnyk.
Film roles include Jaqueline Gill in The Scarehouse (2014), Mary in My Ex-Ex (2015), and Victoria Burns in Definition of Fear (2015).
Her production company, Kit Media, has produced several short films and her 2013 comedy short Issues was recognized as one of the top short films of the year by Richard Crouse. She currently has two feature films in development scheduled for production in 2017.